Ascendent challange,

So i did the aacendent challange we beat the boss, opened the chest then were sent back into tje cave where the portal was gave me the triumph but the bountys not complete at all? Wth also never got my engram from the challange and i did several nightfalls

The reason your bounty did not complete is because you have last weeks' bounty (you can tell from the amount of time remaining, and the Toland qoute). Each weeks' Ascendant Challenge bounty can only be completed by doing the challenge from that week. If you carry it over into the next week, you have to delete it, and pick up the current one from Petra in order to complete the challenge for the week.